Source code for dolfinx.fem.form

# -*- coding: utf-8 -*-
# Copyright (C) 2017-2018 Chris N. Richardson, Garth N. Wells and Michal Habera
#
# This file is part of DOLFINx (https://www.fenicsproject.org)
#
# SPDX-License-Identifier:    LGPL-3.0-or-later

import cffi
import ufl
from dolfinx import cpp, jit


[docs]class Form: def __init__(self, form: ufl.Form, form_compiler_parameters: dict = {}, jit_parameters: dict = {}): """Create DOLFINx Form Parameters ---------- form Pure UFL form form_compiler_parameters See :py:func:`ffcx_jit <dolfinx.jit.ffcx_jit>` jit_parameters See :py:func:`ffcx_jit <dolfinx.jit.ffcx_jit>` Note ---- This wrapper for UFL form is responsible for the actual FFCx compilation and attaching coefficients and domains specific data to the underlying C++ Form. """ # Extract subdomain data from UFL form sd = form.subdomain_data() self._subdomains, = list(sd.values()) # Assuming single domain domain, = list(sd.keys()) # Assuming single domain mesh = domain.ufl_cargo() if mesh is None: raise RuntimeError("Expecting to find a Mesh in the form.") # Compile UFL form with JIT ufc_form = jit.ffcx_jit( mesh.mpi_comm(), form, form_compiler_parameters=form_compiler_parameters, jit_parameters=jit_parameters) # For every argument in form extract its function space function_spaces = [ func.ufl_function_space()._cpp_object for func in form.arguments() ] # Prepare coefficients data. For every coefficient in form take # its C++ object. original_coefficients = form.coefficients() coeffs = [original_coefficients[ufc_form.original_coefficient_position[ i]]._cpp_object for i in range(ufc_form.num_coefficients)] # Create dictionary of of subdomain markers (possible None for # some dimensions subdomains = {cpp.fem.IntegralType.cell: self._subdomains.get("cell"), cpp.fem.IntegralType.exterior_facet: self._subdomains.get("exterior_facet"), cpp.fem.IntegralType.interior_facet: self._subdomains.get("interior_facet"), cpp.fem.IntegralType.vertex: self._subdomains.get("vertex")} # Prepare dolfinx.cpp.fem.Form and hold it as a member ffi = cffi.FFI() self._cpp_object = cpp.fem.create_form(ffi.cast("uintptr_t", ffi.addressof(ufc_form)), function_spaces, coeffs, [c._cpp_object for c in form.constants()], subdomains, mesh)